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Related papers: Classical Universe Arising from Quantum Cosmology

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We analyze the canonical quantum dynamics of the isotropic Universe in a metric approach by adopting a self-interacting scalar field as relational time. When the potential term is absent we are able to associate the the expanding and…

General Relativity and Quantum Cosmology · Physics 2023-09-15 Eleonora Giovannetti , Fabio Maione , Giovanni Montani

Conceptually different from the decoherence program, we present a novel theoretical approach to macroscopic realism and classical physics within quantum theory. It focuses on the limits of observability of quantum effects of macroscopic…

Quantum Physics · Physics 2011-11-09 Johannes Kofler , Caslav Brukner

The correct quantum description for a curvature squared term in the action can be obtained by casting the action in the canonical form with the introduction of a variable which is the negative of the first derivative of the field variable…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. K. Sanyal , B. Modak

A quantization of field theory based on the DeDonder-Weyl covariant Hamiltonian formulation is discussed. A hypercomplex extension of quantum mechanics, in which the space-time Clifford algebra replaces that of the complex numbers, appears…

High Energy Physics - Theory · Physics 2009-10-31 I. V. Kanatchikov

We analyze the quantization of the Pais-Uhlenbeck fourth order oscillator within the framework of deformation quantization. Our approach exploit the Noether symmetries of the system by proposing integrals of motion as the variables to…

Quantum Physics · Physics 2015-10-06 Jasel Berra-Montiel , Alberto Molgado , Efraín Rojas

Deformation quantization is applied to quantize gravitational systems coupled with matter. This quantization procedure is performed explicitly for quantum cosmology of these systems in a flat minisuper(phase)space. The procedure is employed…

High Energy Physics - Theory · Physics 2015-05-30 Ruben Cordero , Erik Diaz , Hugo Garcia-Compean , Francisco J. Turrubiates

In this paper, we investigate the time evolution of quantum coherence -- the off-diagonal elements of the density matrix of a multistate quantum system -- from the perspective of the Wigner-Moyal formalism. This approach provides an exact…

Quantum Physics · Physics 2023-09-18 Austin T. Green , Craig C. Martens

In this work the homogeneous and isotropic Universe of Friedmann-Robertson-Walker is studied in the presence of two fluids: stiff matter and radiation described by the Schutz's formalism. We obtain to the classic case the behaviour of the…

General Relativity and Quantum Cosmology · Physics 2017-10-18 F. G. Alvarenga , R. Fracalossi , R. C. Freitas , S. V. B. Gonçalves

We study a quantization via fractional derivative of a nonminimal derivative coupling cosmological theory, namely, the Fab Four John theory. Its Hamiltonian version presents the issue of fractional powers in the momenta. That problem is…

General Relativity and Quantum Cosmology · Physics 2020-05-08 Isaac Torres , Júlio César Fabris , Oliver Fabio Piattella , Antônio Brasil Batista

We canonically quantize the dynamics of the brane universe embedded into the five-dimensional Schwarzschild-anti-deSitter bulk space-time. We show that in the brane-world settings the formulation of the quantum cosmology, including the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. Boyarsky , A. Neronov , I. Tkachev

We adopt the general formalism, which was developed in Paper I (arXiv:0708.1233) to analyze the evolution of a quantized time-dependent oscillator, to address several questions in the context of quantum field theory in time dependent…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Gaurang Mahajan , T. Padmanabhan

We offer a new proposal for cosmic singularity resolution based upon a quantum cosmology with a unitary bounce. This proposal is illustrated via a novel quantization of a mini-superspace model in which there can be superpositions of the…

General Relativity and Quantum Cosmology · Physics 2018-12-17 Sean Gryb , Karim P. Y. Thébault

The formalism of generalized Wigner transformations developped in a previous paper, is applied to kinetic equations of the Lindblad type for quantum harmonic oscillator models. It is first applied to an oscillator coupled to an equilibrium…

Quantum Physics · Physics 2007-05-23 C. Tzanakis , A. P. Grecos , P. Hatjimanolaki

We consider a Schr\"odinger quantum dynamics for the gravitational field associated to a generic cosmological model and then we solve the corresponding eigenvalue problem. We show that, from a phenomenological point of view, an Evolutionary…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marco Valerio Battisti , Giovanni Montani

The relationship between classical and quantum theory is of central importance to the philosophy of physics, and any interpretation of quantum mechanics has to clarify it. Our discussion of this relationship is partly historical and…

Quantum Physics · Physics 2007-05-23 N. P. Landsman

We implement the so-called Weyl-Heisenberg covariant integral quantization in the case of a classical system constrained by a bounded or semi-bounded geometry. The procedure, which is free of the ordering problem of operators, is…

Quantum Physics · Physics 2019-11-04 J. -P. Gazeau , T. Koide , D. Noguera

The algebra of generalized linear quantum canonical transformations is examined in the prespective of Schwinger's unitary-canonical basis. Formulation of the quantum phase problem within the theory of quantum canonical transformations and…

Quantum Physics · Physics 2008-11-26 T. Hakioglu

Quantum cosmology is the quantum theory of the entire universe. Although strange at first sight, it is appropriate because (1) our world appears to be fundamentally quantum, (2) the classical description of gravity breaks down at…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Don N. Page

This work applies the principles of quantum cosmology to examine models incorporating a quintom field. Specifically, three distinct models are analyzed: a simplified toy model, a model featuring an exponential quintom potential, and one…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Behzad Tajahmad

We discuss the cosmological evolution of the Weyl conformal geometry and its associated Weyl quadratic gravity. The Einstein gravity (with a positive cosmological constant) is recovered in the spontaneously broken phase of Weyl gravity;…

General Relativity and Quantum Cosmology · Physics 2022-06-24 D. M. Ghilencea , T. Harko